Natural leather is a durable skin wrapping animals' body. Due to its outstanding physical properties, it is widely used in various fields, such as bags, shoes and furniture. The natural leather is separated from the animals' body and processed through chemical and physical procedures for an end product. During various processing, it is essential to cut in accordance with the design of the desired product. Because of the cutting process, a large amount of leather wastes occurs. Since most of these wastes are disposed at facilities for combustion or landfill, environmental problems arise seriously.
Thus, various studies are being carried out to recycle burned or landfilled leather wastes. As part of such efforts, technology has been developed for grinding leather wastes and preparing artificial leather using synthetic resin adhesive. A related patent is Republic of Korea Patent No. 10-1022828 (A dry synthetic leather, a manufacturing method and a manufacturing system therefor, Mar. 3, 2011.).
However, the above technology grinds leather wastes and uses synthetic resin adhesive to prepare recycling leather sheets. Accordingly, there is a limitation that environmental pollution still exists due to toxic gas generated during hardening, heating and rolling the synthetic resin adhesive.
Therefore, new needs for a method of preparing recycling leather sheets that may reduce environmental pollution have arisen.